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Abstract:

An apparatus for delivering a volatile material in a continuous manner is
disclosed. The apparatus includes a delivery engine having a reservoir
for containing a volatile material; a rupturable substrate secured to the
reservoir; a rupture element positioned adjacent to the rupturable
substrate; and a breathable membrane enclosing the reservoir, rupturable
substrate and rupture element. In some embodiments, the apparatus
includes a housing having a notch for compressing the rupture element and
breaching the rupturable substrate as it is inserted into the housing.

Claims:

1. An apparatus for delivering a volatile material comprising a delivery
engine comprising: a. a reservoir comprising a volatile material mixture,
said mixture comprising about 90% to about 100%, by total, weight of said
mixture, of volatile materials each having a VP at 25.degree. C. of less
about 0.3 torr. b. a rupturable substrate secured to said reservoir; c. a
rupture element positioned adjacent to said rupturable substrate; and d.
a microporous, ultra-high molecular weight polyethylene membrane
enclosing said reservoir, said rupturable substrate, and said rupture
element, wherein said membrane comprises an average pore size of about
0.01 microns to about 0.06 microns and comprises a thickness of about
0.01 mm to about 1 mm.

2. The apparatus of claim 1, wherein said delivery engine further
comprises a collection basin in fluid communication with said microporous
membrane and said reservoir upon rupturing said rupturable substrate.

3. (canceled)

4. The apparatus of claim 1, wherein said rupture element is positioned
between said rupturable substrate and said microporous membrane.

5. The apparatus of claim 1, wherein said rupture element is positioned
subjacent said microporous membrane.

8. The apparatus of claim 7, wherein said compressible flange comprises a
distal end and a piercing element, said piercing element positioned on
said distal end.

9. The apparatus of claim 1, wherein the compression force of said
rupture element to breath said rupturable substrate is less than about 15
N.

10. The apparatus of claim 1, wherein said macroporous membrane comprises
an average pore size of about 0.01 to about 0.03 microns.

11. The apparatus of claim 1, wherein said microporous membrane comprises
an average pore size of about 0.02 microns.

12. The apparatus of claim 1, wherein the evaporative surface area of
said microporous membrane is about 15 cm2 to about 35 cm.sup.2.

13. The apparatus of claim 1, further comprising a housing comprising a
base, a shell, and a hollowed core.

14. The apparatus of claim 13, wherein said hollowed core comprises a
notch for compressing said rupture element upon insertion of said
delivery engine in said housing.

15. The apparatus of claim 14 wherein said hollowed core comprises a
front wall comprising vents, wherein said notch is positioned on the
inner face of said front wall.

16. The apparatus of claim 14 wherein said hollowed core comprises a
first rib and a second rib for guiding said delivery engine against said
notch.

17. The apparatus of claim 13, wherein said housing comprises intensity
control means.

18. An apparatus for delivering a volatile material comprising a delivery
engine comprising: a. a liquid reservoir comprising a volatile material
mixture, said mixture comprising about 90% to about 100%, by total weight
of said mixture, of volatile materials each having a VP at 25.degree. C.
of less than about 0.3 torr; b. a rupturable substrate secured to said
reservoir; c. a compressible flange positioned adjacent to said
rupturable substrate for rupturing said rupturable substrate; d. a
collection basin in fluid communication with said liquid reservoir upon
rupturing said rupturable substrate; and e. a microporous, ultra-high
molecular weight polyethylene membrane enclosing said liquid reservoir,
said rupturable substrate, said rupture element, and said collection
basin, wherein said membrane comprises an average pore size of about 0.01
microns to about 0.06 microns and comprises a thickness of about 0.01 mm
to about 1 mm.

19. The apparatus of claim 18, wherein said compressible flange comprises
a distal end and a piercing element, said piercing element positioned on
said distal end.

20. The apparatus of claim 18, wherein the compression force of said
rupture element to breach said rupturable substrate is less than about
15N.

21. The apparatus of claim 18, wherein said breathable membrane comprises
an evaporative surface area of about 15 cm2 to about 35 cm2

22. An apparatus for delivering a volatile material comprising: a. a
delivery engine comprising: i. a liquid reservoir comprising a single
opening and comprising a width to length ratio of about 4:1 and a depth
of about s mm to about 15 mm. and a volatile material mixture. said
mixture comprising about 90% to about 100%, by total weight of said
mixture, of volatile materials each having a VP at 25.degree. C. of less
than about 0.3 torr; ii. a rupturable substrate enclosing said single
opening; iii. a rupture element; iv. a collection basin in fluid
communication with said liquid reservoir upon rupturing said rupturable
substrate; v. a microporous, ultra-high molecular weight polyethylene
membrane sealed to said liquid reservoir and enclosing said rupturable
substrate, said rupture element, and said collection basin, wherein said
breathable membrane comprises an evaporative surface area of about 15
cm2 to about 35 cm2 and comprises an average pore size of about
0.02 microns and comprises a thickness of about 0.01 mm to about 1 mm;
and b. a housing comprising a notch for compressing said rupture element
upon insertion of said delivery engine into said housing.

23. The apparatus of claim 22, wherein the insertion force of said
delivery engine in said housing to breach said rupturable substrate is
less than about 25N.

Description:

FIELD OF THE INVENTION

[0001] The present invention relates to an apparatus having a breathable
membrane for delivering a volatile material to the atmosphere in a
continuous manner.

BACKGROUND OF THE INVENTION

[0002] It is generally known to use a device to evaporate a volatile
material into a space, particularly a domestic space, in order to deliver
a variety of benefits, such as air freshening or perfuming of the air.
Non-energized systems, for example, systems that are not powered by
electrical energy, are a popular way for the delivery of volatile
materials into the atmosphere. These systems can be classified into those
that require human actuation, such as aerosols, and those which do not
required human actuation, such as wick based systems and gels. The first
type delivers the volatile materials on demand and the second type in a
more continuous manner.

[0003] One type of apparatus for delivering a volatile material is
disclosed in U.S. Pat. No. 4,161,283. It discloses an article for
delivering a volatile material comprising a reservoir, polymeric sheet or
membrane, and a barrier layer releasably bonded to the outer wall of the
reservoir. One drawback with this type of article is its susceptibility
to de-lamination and leakage because the volatile materials are in
contact with the membrane during storage or non-use. Another drawback may
be that volatile materials build up in the membrane during storage,
resulting in a spike in intensity immediately after the barrier layer is
removed. Another drawback may be that the peel force makes it is
difficult to remove the barrier layer without damaging the polymeric
sheet or membrane. Yet another drawback may be the selectivity of the
membrane in that it does not easily allow low vapor pressure volatile
materials to diffuse through the polymer.

[0004] Another apparatus for delivering a volatile material is disclosed
in U.S. Pat. No. 4,824,707. It discloses a decorative air freshener unit
having a capsule containing a supply of volatile fragrance. The capsule
is trapped between a microporous sheet and a backing sheet. The capsule
is ruptured by applied force and the released fragrance is absorbed into
the microporous sheet which gradually exudes the fragrance. This approach
may limit the longevity of a scent since liquid is released all at once
to the microporous sheet, and there is little control over the manner in
which the liquid will wet the microporous sheet.

[0005] As such, there exists a need for an apparatus for delivering, over
a period of time, a consistent release of volatile materials having a
broad range of molecular weights and vapor pressures.

SUMMARY OF THE INVENTION

[0006] According to one embodiment of the invention, there is provided an
apparatus for delivering a volatile material comprising a delivery engine
having a reservoir for containing a volatile material; a rupturable
substrate secured to the reservoir; a rupture element positioned adjacent
to the rupturable substrate; and a microporous membrane enclosing the
reservoir, rupturable substrate, and rupture element. The apparatus may
deliver a volatile material in a continuous manner. In one aspect of the
invention, the apparatus comprises a housing for the delivery engine. The
housing may have vents for facilitating the diffusion of volatile
materials from the delivery engine.

[0007] According to another embodiment of the invention, there is provided
an apparatus for delivering a volatile material comprising a delivery
engine having a liquid reservoir for containing a volatile material; a
rupturable substrate secured to the reservoir; a compressible flange
positioned adjacent to the rupturable substrate for rupturing the
rupturable substrate; a collection basin in fluid communication with the
liquid reservoir upon rupturing the rupturable substrate; and a
breathable membrane enclosing the liquid reservoir, rupturable substrate,
rupture element, and collection basin.

[0008] According to yet another embodiment of the invention, there is
provided an apparatus for delivering a volatile material comprising a
delivery engine having a liquid reservoir for containing a volatile
material comprising a single opening; a rupturable substrate enclosing
the single opening; a rupture element; a collection basin in fluid
communication with the liquid reservoir upon rupturing the rupturable
substrate; and a breathable membrane enclosing the liquid reservoir,
rupturable substrate, rupture element, and collection basin. The
breathable membrane has an evaporative surface area of about 15 cm2
to about 35 cm2 and has an average pore size of about 0.02 microns.
The apparatus also comprises a housing for receiving and releasably
engaging the delivery system. The housing has a rib for guiding the
delivery engine and a notch for compressing the rupture element upon
insertion of the delivery engine into the housing.

BRIEF DESCRIPTION OF THE DRAWINGS

[0009] While the specification concludes with the claims particularly
pointing out and distinctly claiming the invention, it is believed that
the present invention will be better understood from the following
description taken in conjunction with the accompanying drawings in which:

[0010] FIG. 1 shows a perspective view of one embodiment of an apparatus
in accordance with the present invention.

[0011]FIG. 2 shows an exploded, perspective view of one embodiment of a
delivery engine in accordance with the present invention.

[0012]FIG. 3 shows a cross-sectional view of another embodiment of a
rupture element in accordance with the present invention.

[0013] FIG. 4 shows a cross-sectional view of another embodiment of a
rupture element in accordance with the present invention.

[0014] FIG. 5 shows a side elevational view of the delivery engine in FIG.
2 in accordance with the present invention.

[0015]FIG. 6 shows a front elevational view of one embodiment of a
housing in accordance with the present invention.

[0017] FIG. 8 shows a cross-sectional view along lines 8-8 of the
apparatus in FIG. 1.

[0018]FIG. 9 shows the cross-sectional view in FIG. 8 where the delivery
engine is being received by the housing.

[0019] FIG. 10 is a graph showing evaporation profiles of volatile
materials having varying vapor pressure ranges evaporated from a
breathable membrane in accordance with the present invention

[0020] FIG. 11 is a graph showing evaporation profiles of volatile
materials evaporated from a polyethylene membrane and from a breathable
membrane in accordance with the present invention.

DETAILED DESCRIPTION OF THE INVENTION

[0021] The present invention relates to a non-energized apparatus for the
delivery of a volatile material to the atmosphere in a continuous,
non-energized manner. "Non-energized" means that the apparatus is passive
does not require to be powered by a source of external energy. In
particular, the apparatus does not need to be powered by a source of
heat, gas, or electrical current, and the volatile material is not
delivered by aerosol means. Further, as used in this specification and
the appended claims, the singular forms "a", "an", and "the" include
plural references unless the content clearly dictates otherwise. Thus,
for example, "a volatile material" may include more than one volatile
material

[0022] The apparatus of the present invention delivers a volatile material
in a substantially continuous manner when the apparatus is in a resting
position (i.e. the apparatus is not being moved). The emission level of
volatile materials may exhibit a uniform intensity until substantially
all the volatile materials are exhausted. The continuous emission of the
volatile materials can be of any suitable length, including but not
limited to, up to: 20 days, 30 days, 60 days, 90 days, shorter or longer
periods, or any period between 30 to 90 days.

[0023] The apparatus of the present invention is suitable for purposes of
providing fragrances, air fresheners, deodorizers, odor eliminators,
malodor counteractants, insecticides, insect repellants, medicinal
substances, disinfectants, sanitizers, mood enhancers, and aromatherapy
aids, or for any other purpose using a volatile material that acts to
condition, modify, or otherwise change the atmosphere or the environment.
For purposes of illustrating the present invention in detail, but without
intending to limit the scope of the invention, the invention will be
described in an air freshening system for delivering liquid containing
perfume raw materials.

[0024] Referring to FIG. 1, an apparatus 10 in accordance with the present
invention is shown. The apparatus 10 includes a delivery engine 100 and a
housing 200.

Delivery Engine

[0025] Referring to FIG. 2, the delivery engine 100 comprises a width,
length and depth along an x-axis, y-axis, and z-axis, respectively. The
width, length, and depth may be such that the delivery engine 100 is
considered compact and/or portable. By "compact" or "portable", it is
meant that the delivery engine 100 can be conveniently and comfortably
carried in a pocket, purse, or the like. The delivery engine 100 can be
constructed as a disposable, single-use item or one that it is
replenished with a volatile material.

[0026] The delivery engine 100 may include a lip 102 that defines the
outer perimeter of the delivery engine 100 and may circumference a
reservoir 110 for containing a volatile material as well as a collection
basin 112. The delivery engine 100 may also include a rupturable
substrate 120 secured to the reservoir 110; a rupture element 130
positioned adjacent to the rupturable substrate 120; and a breathable
membrane 140 secured to the lip 102 and enclosing the rupturable
substrate 120, reservoir 110, and collection basin 112.

[0027] The body 104 of the delivery engine 100 can be thermoformed,
injection molded, or blow molded with any known material. In some
embodiments, the body 104 includes all structural aspects of the delivery
engine 100 minus the rupturable substrate 120, the rupture element 130,
and breathable membrane 140. In other embodiments, the body 104 includes
the rupture element 130. The body 104 may be made of a multi layer
material which may include a barrier layer to prevent evaporation of a
volatile component and at least one outer layer that allows a rupturable
substrate 120 to be heat-sealed to the body 104. A suitable sealant layer
would include a layer of polyethylene or polypropylene or any suitable
polyolefin sealant that allows for a leak proof seal of the reservoir
110. Suitable materials to form the body 104 of the delivery engine 100
include plastics, such as Pentaplast Pentaform® 2101 available from
Klockner. In some embodiments, the material is colored or non-colored
see-through plastic. The see-through material permits observation of the
liquid and end-of life.

[0028] Reservoir

[0029] The delivery engine 100 may comprise a reservoir 110 for holding a
volatile material. The reservoir 110 includes a width, length, and depth
along the x-axis, y-axis, and z-axis, respectively. The reservoir 110 may
be elongate in that its width to length ratio is about 2:1 to about 4:1,
alternatively about 1.5:1 to about 2.5:1. The reservoir 110 may have a
width of about 45 mm to about 55 mm, alternatively about 51 mm; a length
of about 15 mm to about 30 mm to about, alternatively about 23 mm; a
depth of about 5 mm to about 15 mm, alternatively about 11 mm. The
dimensions of the reservoir 110 may be such that it holds about 2 ml to
about 50 ml of liquid containing a volatile material. Alternatively, the
reservoir 110 may hold about 2 ml to about 30 ml, alternatively about 2
ml to about 10 ml, alternatively about 2 ml to about 8 ml, alternatively
about 4 ml to about 6 ml, alternatively about 2 ml, alternatively about 6
ml of liquid containing a volatile material.

[0030] The reservoir 110 may include a bottom 114 and a single opening
116. The reservoir 110 may also have a ridge 122 circumferencing the
single opening 116 or the upper edge of the reservoir 110. This ridge 122
may provide a generally flat surface upon which a rupturable substrate
120 may be secured. The ridge 122 allows the secured area of the
rupturable substrate 120 to be located away from the inner walls of the
reservoir 110 where the volatile material would be held.

[0031] It is contemplated that the delivery engine 100 of the present
invention may comprise two or more reservoirs (not shown) which can be
filled with the same or different volatile materials. The reservoirs may
have any configuration that contacts the breathable membrane 140 upon
rupture. For example, the reservoirs may be opposedly connected for use
in a flippable device. In such a device, the breathable membrane 140 is
fluidly connected between the reservoirs.

[0032] Rupturable Substrate

[0033] Still referring to FIG. 2, the delivery engine 100 includes a
rupturable substrate 120. The rupturable substrate 120 may be configured
in any manner that prevents the volatile material in the reservoir 110
from contacting the breathable membrane 140 prior to activating or
rupturing the delivery engine 100. In one embodiment, the rupturable
substrate 120 may enclose the reservoir, prior to activation, by
extending across the single opening 116 securing to the ridge 122 of the
reservoir 110. The rupturable substrate 120 may be secured by a layer of
adhesives, heat and/or pressure sealing, ultrasonic bonding, crimping,
and the like or a combination thereof.

[0034] The rupturable substrate 120 can be made of any material that
ruptures with applied force, with or without the presence of an element
to aid in such rupture. Because the rupturable substrate 120 is intended
to contain a volatile material while in storage, it may be made from a
layer of barrier material that prevents evaporation of the volatile
material prior to its intended use and a layer of heat-sealable layer.
Such materials may be impermeable to vapors and liquids. Suitable barrier
materials for the rupturable substrate 120 include a flexible film, such
as a polymeric film, a flexible foil, or a composite material such as
foil/polymeric film laminate. Suitable flexible foils include a metal
foil such as a foil comprised of a nitrocellulose protective lacquer, a
20 micron aluminum foil, a polyurethane primer, and 15 g/m2 polyethylene
coating (Lidfoil 118-0092), available from Alcan Packaging. Suitable
polymeric films include polyethylene terephtalate (PET) films,
acrylonitrile copolymer barrier films such as those sold under the
tradename Barex® by INOES, ethylene vinyl alcohol, and combinations
thereof. It is also contemplated that coated barrier films may be
utilized as a rupturable substrate 120. Such coated barrier films include
metalized PET, metalized polypropylene, silica or alumina coated film may
be used. Any barrier material, whether coated or uncoated, may be used
alone and or in combination with other barrier materials.

[0035] Rupture Element

[0036] The rupturable substrate 120 may be breached to release a volatile
material by actuating a rupture element 130. The rupture element 130 can
be injection, compression, or pressure molded using a polyolefin, such as
polyethylene or polypropylene; polyester; or other plastics as known to
be suitable for molding. The rupture element 130 could also be made by
thermoforming with a discrete cutting step to remove parts not wanted.

[0037] The rupture element 130 may be positioned in a space 132 formed in
the delivery engine body 104 that is adjacent to the rupturable substrate
120 and subjacent a breathable membrane 140. The space 132 may be
configured such that the rupture element 132 is nested within the space
132 and enclosed by a breathable membrane 140, thus requiring no other
means to hold the rupture element 132 in the delivery engine 100. In one
embodiment, the rupture element 130 is positioned between and in contact
with said rupturable substrate 120 and said breathable membrane 140. A
rupture element 130 that is directly adjacent to the breathable membrane
140 may facilitate wetting of the breathable membrane 140. More
specifically, liquid may wick between rupture element 130 and the
breathable membrane 140 allowing for maintenance of a larger wetted
surface area of the breathable membrane 140.

[0038] The rupture element 130 may be configured in any manner such that a
user can manually actuate the rupture element 130 and breach the
rupturable substrate 120 with relative ease. In one embodiment, a user
may actuate the rupture element 130 by manually compressing it. In other
embodiments, the rupture element 130 may breach the rupturable substrate
120 through contact with an element provided in a delivery engine housing
that engages and compresses the rupture element 130. Suitable compression
forces to breach the rupturable substrate 120 with a rupture element 130
may be less than about 25N, alternatively, less than about 20N,
alternatively less than about 15N, alternatively less than about 10N,
alternatively less than about 5N, alternatively from about 1N to about
15N, alternatively, from about 1N, to about 10N, alternatively, from
about 1N to about 5N.

[0039] The compression force can be measured using an electromechanical
testing system, QTest Elite 10, available from MTS, along with a modified
UL 283 finger probe made of polyamide. The UL 283 finger probe is
described in Standard for Air Fresheners and Deodorizers, UL Standard
283, FIG. 10.1 (UL Mar. 31, 2004). As described in UL 283, FIG. 10.1, the
radius of the finger tip is 3.5 mm; height of the finger tip is 5 mm;
depth of the finger tip is 5.8 mm. However, unlike the finger probe
described in the aforementioned text, the modified UL 283 finger probe
does not include any articulating joints. Instead, it is in a fixed
position that is perpendicular to the rupture element 130 when testing is
conducted. The testing occurs at ambient temperatures (23±2°
C.). The perimeter of a delivery engine 100 is rested on a support
fixture, without directly contacting or directly securing the rupture
element 130 to the support fixture. The crosshead speed of the
electromechanical testing system is set at 30 mm/min. The modified UL 283
finger probe is moved towards the rupture element 130 to contact a region
where displacement is desired for rupturing a rupturable substrate 120.
Where a flange 134 such as the one described herein is utilized, the
desired region of displacement is the mid-point of the flange 134. The
mid-point is the point that is half way between the proximal end and
distal end 136. For example, where a flange 134 is 2 cm from proximal end
to distal end 136, the mid-point is located at 1 cm. The machine is run
until the rupture element 130 is displaced by 6 mm. Zero displacement is
defined as the point at which 0.1N of force (i.e. preload) is applied.
The load at the first peak where the rupturable substrate 120 is broken
is recorded as the force to rupture. Those of ordinary skill in the art
will appreciate that compression forces will vary depending on the
physical properties and placement of the breathable membrane 140, rupture
element 130, and rupturable substrate 120 in a delivery engine 100.

[0040] There are numerous embodiments of the rupture element 130 described
herein, all of which are intended to be non-limiting examples. FIG. 2
shows one non-limiting embodiment of the rupture element 130. In this
embodiment, the rupture element 130 includes a flange 134 hinged to the
rupture element 130. The flange 134 may be injection molded and may
include a distal end 136. The distal end 136 may include one or more
piercing elements 138 located in the z-direction or towards the
rupturable substrate 120. In one embodiment, the distal end 136 may
include two spaced apart piercing elements 138 in the z-direction. In an
alternate embodiment, the distal end 136 may form a single point (not
shown) along the x-y plane. A user may manually compress or press
downward in the z-direction on the flange 134 such that the rupturable
substrate 120 is breached and a volatile material is released to the
breathable membrane 140.

[0041] It is contemplated that the rupture element 130 may include more
than one flange 134 where additional points of rupture are desired. For
example, the rupture element 130 may include a first compressible flange
and a second compressible flange opposedly hinged to said rupture element
(not shown).

[0042]FIG. 3 shows another embodiment of a rupture element 330 which
includes one or more piercing elements 332 supported on a corresponding
spring-like part 334. The spring-like part 334 may be a metal coil,
polyolefin or polyurethane foam, injection molded bristles, injection
molded plastic spring or hinge parts, or the like. Upon pressing the
rupture element 330 towards the rupturable substrate 320, one or more
piercing elements 332 will puncture the rupturable substrate 320 and then
return to its original position.

[0043] FIG. 4 shows another embodiment of a rupture element 430 where it
is integrally formed with the reservoir 410. This can be accomplished by
thermoforming, pressure forming, injection molding or any known means of
forming plastic parts. The rupture element 430 in this embodiment, is a
sharp piercing structure extending opposite from the interior bottom 414
of the reservoir. A user may compress the bottom 414 of the reservoir 410
to pierce the rupturable substrate 420 with the rupture element 430. This
embodiment eliminates having to manufacture a separate rupture element
430, yet it performs the same function.

[0044] Collection Basin

[0045] Now referring to FIG. 5, the delivery engine 100 may optionally
include a collection basin 112 to collect volatile materials from the
reservoir 110 after the rupturable substrate 120 is compromised. The
collection basin 112 may be any size, shape or configuration, and may be
made of any suitable material, so long as it is in fluid communication
with the reservoir 110 and the breathable membrane 140 upon rupturing the
rupturable substrate 120. It may be sized to collect any suitable volume
of a volatile material to provide a controlled volume of the volatile
material to the breathable membrane 140. In one embodiment, the
collection basin 112 may be sized to collect about 1 ml to about 4 ml of
volatile materials, alternatively about 1 ml to about 3 ml, alternatively
about 1 ml to about 2.5 ml, alternatively about 1.5 ml to about 1.8 ml.

[0046] In one embodiment, the collection basin 112 may include a bottom
118 in the z-direction and a top that opens towards a breathable membrane
140. The breathable membrane 140 may lie across the open top, enclosing
the collection basin 112 so liquid cannot flow freely out through the
breathable membrane 140. The collection basin 112 may be integrally
constructed with the body 104 of the delivery engine 100 in a thermoform
part.

[0047] As shown in FIG. 5, in one embodiment, the collection basin 112 is
positioned downwardly or opposite the y-direction from the reservoir 110.
When the delivery engine 100 is placed upright, a volatile material
naturally flows down the reservoir 110 into the collection basin 112
ensuring a controlled, continual dosing of the breathable membrane 140.
Further, the collection basin 112 has depth along the z-axis which is
smaller in depth than the reservoir 110. The bottom 118 of the collection
basin lies closer to the breathable membrane 140 than the reservoir
bottom 114, thus forming a step in the delivery engine 100. The proximity
of the collection basin bottom 118 with the breathable membrane 140 helps
to ensure a continual supply of volatile material and wet more surface
area of the breathable membrane 140, even when very little volatile
material remains in the delivery engine 100. When the liquid contact area
of the breathable membrane 140 is greater, the evaporation rate of
volatile materials is higher and fragrance intensity can be maintained
over longer periods.

[0048] Membrane

[0049] The delivery engine 100 may include a breathable membrane 140. The
breathable membrane 140 is vapor permeable and prevents free flow of
liquid out of the membrane 140, thus addressing leakage problems.

[0050] The breathable membrane 140 may be secured to the lip 102 of the
delivery engine 100 in the same manner as the rupturable substrate 120 is
secured to the ridge 122 of the reservoir 110. The breathable membrane
140 encloses the reservoir 110, rupturable substrate 120, rupture element
130, and collection basin 112. In this way, the rupturable substrate 120
may be breached by compressing the breathable membrane 140 and the
rupture element 130. Once breached, the volatile material flows out of
the reservoir 110, contacts the breathable membrane 140, and is delivered
to the atmosphere. Because the breathable membrane 140 is shielded from
the volatile material until the rupturable substrate 120 is breached, the
fragrance intensity may build slowly from zero to its equilibrium rate of
release when the breathable membrane 140 is fully wetted.

[0051] While not wishing to be bound by theory, the physical
characteristics of a membrane may affect the diffusion rate of volatile
materials through the membrane. Such characteristics may include
materials used, pore size, thickness, and evaporative surface area.

[0052] The breathable membrane 140 may be filled with any suitable filler
and plasticizer known in the art. Fillers may include finely divided
silica, clays, zeolites, carbonates, charcoals, and mixtures thereof. In
one embodiment, the breathable membrane 140 may be filled with about 50%
to about 80%, by total weight, of silica, alternatively about 60% to
about 80%, alternatively about 70% to about 80%, alternatively about 70%
to about 75%.

[0053] In one embodiment, the breathable membrane 140 may include a
microporous membrane. The microporous membrane is vapor permeable and
capable of wicking liquid, yet prevents free flow of liquid out of the
membrane. The microporous membrane may have limited selectivity leaving
behind fewer perfume materials. Membranes that are selective, such as
traditional polyethylenes, may inhibit high molecular weight volatile
materials and materials with low solubility in polyethylene from
diffusing through. This may limit perfume formulations, for example in
the field of air fresheners where it is typically desired to use
formulations having a wide variety of volatile materials having different
volatilities. For example, some membranes may preclude the diffusion of
alcohols, such as linalool and dihydromyrcenol which are widely used in
perfume applications. The microporous membrane may have an average pore
size of about 0.01 to about 0.06 microns, alternatively from about 0.01
to about 0.05 microns, alternatively about 0.01 to about 0.04,
alternatively about 0.01 to about 0.03, alternatively about 0.02 to about
0.04 micron, alternatively about 0.02 microns.

[0054] The breathable membrane 140 may have a thickness in the
z-direction, of about 0.01 mm to about 1 mm, alternatively between about
0.1 mm to 0.4 mm, alternatively about 0.15 mm to about 0.35 mm,
alternatively about 0.25 mm.

[0055] Those of ordinary skill in the art will appreciate that the surface
area of the breathable membrane 140 can vary depending on the user
preferred size of the delivery engine 100. In some embodiments, the
evaporative surface area of the breathable membrane 140 may be about 2
cm2 to about 100 cm2, alternatively about 10 cm2 to about
50 cm2, alternatively about 10 cm2 to about 45 cm2,
alternatively about 10 cm2 to about 35 cm2, alternatively about
15 cm2 to about 40 cm2, alternatively about 15 cm2 to
about 35 cm2, alternatively about 20 cm2 to about 35 cm2,
alternatively about 30 cm2 to about 35 cm2, alternatively about
35 cm2.

[0056] Suitable breathable membranes 140 for the present invention include
a microporous, ultra-high molecular weight polyethylene (UHMWPE)
optionally filled with silica as described in U.S. Pat. No. 7,498,369.
Such UHMWPE membranes include Daramic® V5, available from Daramic,
Solupor®, available from DSM (Netherlands), and Teslin®, available
from PPG Industries, and combinations thereof. It is believed that these
membranes allow a volatile material to freely dissipate, while containing
liquid within the delivery engine 100.

[0057] Other suitable breathable membranes 140 include any permeable
polymeric, thermoplastic, or thermoset material, including acetal,
acrylic, cellulosic, fluoroplastic, polyamide, polyester, polyvinyl,
polyolefin, styrenic, etc, alone, co-extruded, woven or non-woven, mixed
or in combination with elastomers, rubber, solids, silicas, or
combinations thereof. Also suitable are Hytrel® available from Dupont
or Lotryl® available from Arkema.

[0058] In one aspect of the invention, the breathable membrane 140 may
include a dye that is sensitive to the amount of volatile material it is
in contact with to indicate end-of-life. Alternatively, the breathable
membrane 140 may change to transparent when in contact with a fragrance
or volatile material to indicate diffusion is occurring. Other means for
indicating end-of-life that are known in the art are contemplated for the
present invention.

Housing

[0059] Now referring to FIGS. 6 to 9, the apparatus 10 of the present
invention may include a housing 200 for releasably engaging the delivery
engine 100. The housing 200 may comprise a width, length and depth along
an x-axis, y-axis, and z-axis, respectively (as shown in FIG. 1). The
housing 200 can be made of any suitable material such as glass, ceramic,
wood, plastic, composite material, etc, and can have any size, shape and
configuration suitable for encasing the delivery engine 100. The housing
200 can be rigid or flexible and can be made of material which allows the
transfer of volatile materials to the surrounding environment. The
housing 200 may include a base 210, a hollowed core 240 supported on the
base 210 and nested internally within a shell 220. The housing 200 may
also include a notch 270 and vents 260.

[0060] Shell and Hollowed Core

[0061] As seen in FIGS. 8 and 9, the housing 100 may include a hollowed
core 240 supported on a base 210 and nested internally within a shell
220. The shell 220 may have a front wall 222 and a rear wall 224, both of
which may be generally coextensive with a front wall 242 and a rear wall
244 of the hollowed core 240. The hollowed core 240 and shell 220 may be
elliptically cylindrical and include a receiving end 230 for receiving
the delivery engine 100. The receiving end 230 may be disposed remotely
from the base 210 of the housing 200.

[0062] Ribs and Notches

[0063] The inner face of the rear wall 244 of the hollowed core 240 may
include one or more retaining ribs 246 for guiding the delivery engine
100 downward into its final in-use position as seen in FIG. 9. In one
embodiment, the retaining ribs 246 may include a first retaining rib and
a second retaining rib positioned on the inner face of the rear wall 244
and which both extend longitudinally along the y-axis. The first and
second retaining ribs may be positioned at the intersection of the front
242 and rear walls 244 of the hollowed core 240 to receive the lip 102 of
the delivery engine 100.

[0064] The housing 200 may also include a notch 270, or a plurality of
notches, to engage or compress the rupture element 130 as the delivery
engine 100 is being received in the housing 200. In this way, a user is
not required to manually activate the delivery engine 100 prior to its
insertion into the housing 200. The notch 270 may be configured in any
manner such that the delivery engine 100 can be inserted into the housing
200 with relative ease while the notch 270 compresses the rupture element
130 and breaches the rupturable substrate 120.

[0065] Suitable insertion forces to insert the delivery engine 100 which
compresses the rupture element 130 and breaches the rupturable substrate
120 include less than about 25N, alternatively less than about 20N,
alternatively less than about 15N, alternatively less than about 5N,
alternatively from about 1N to about 25N, alternatively from about 1N to
about 15N, alternatively from about 5N to about 20N, alternatively from
about 5N to about 15N, alternatively about 8 to 15 N.

[0066] The insertion force can be measured using an electromechanical
testing system, QTest Elite 10 available from MTS. The delivery engine
100 is clamped to the testing system and placed in the receiving end of
the housing without any force against any notch 270 or elements that
breach or help breach the rupturable substrate 120. The crosshead speed
of the electromechanical testing system is set at 50 mm/min. The room
temperature is 23±2° C. The machine is run until the rupturable
substrate 120 is breached. Zero displacement is defined as the point at
which 0.1N of force (i.e. preload) is applied. The load at the first peak
where the rupture substrate 120 is broken is recorded as the force to
rupture. Those of ordinary skill in the art will appreciate that
insertion forces will vary depending on the physical properties and
placement of the notch 270, breathable membrane 140, rupture element 130,
and rupturable substrate 120.

[0067] In one embodiment, the notch 270 may be laterally off-set from the
center of the front wall 242 of the hollowed core 240, so that less
projection of the notch 270 in the z-direction is required when
manufacturing. Thus, the breathable membrane 140 does not need to be
stretched as far, resulting in less likelihood of damage.

[0068] The notch 270 and ribs 246 are configured such that the delivery
engine 100 does not need to bend when inserting, resulting in lower
insertion force. As the delivery engine 100 is inserted into the housing
200, the notch 270 compresses the breathable membrane 140 and the rupture
element 130 in the direction of the reservoir 110 to breach the
rupturable substrate 120 and release volatile materials to the breathable
membrane 140. During insertion of the delivery engine 100, the ribs 246
guide the delivery engine 100 into contact and against the notch 270,
maintaining the lateral position of the delivery engine 100 so the notch
270 fully engages the rupture element 130.

[0069] Vents

[0070] The housing 200 may have a plurality of vents 260 or apertures
which align in a first, open position to facilitate delivery of the
volatile material from the breathable membrane 140 to the atmosphere of
the room or rooms that require treatment. Increasing the effective size
of the vents 260, may increase the delivery of volatile material.
Conversely, decreasing the effective size of the vents 260, may decrease
the delivery of volatile material.

[0071] The vents 260 may be disposed anywhere on the housing 200. In the
embodiment shown in FIGS. 6 to 9, the vents 260 are disposed on the front
walls 222, 242 of shell 220 and hollowed core 240. The number and/or size
of the vents 260 are not fixed. The size of the vents 260 can be
controlled by the user through a variety of means. A user may open,
partially open, partially close, or close the one or more vents 260 by
sliding the shell 220 downwardly along the y-axis towards the base 210
such that the desired amount of emission is delivered to the location
needing treatment. The housing 200 may also be constructed to enable open
and closing of the vents 260 by rotation of the shell 240 around the
x-axis (not shown). In addition to the vents 260, the housing 200 may
have other means for visual inspection of the delivery engine 100.

[0072] The housing 200 may also include a clicking mechanism (not shown)
to signal to the user that the housing 200 is in the desired open or
closed position. Such clicking mechanism may include a first mating part
(not shown) disposed along the outer face of the hollowed core 240 and a
second mating part (not shown) disposed along the inner face of the shell
220. The mating parts may frictionally engage the walls of the shell 220
and hollowed core 240 as they slide against one another. When the desired
open or closed position is reached the mating parts may releasably lock
into place and may provide a clicking sound.

Volatile Material

[0073] The apparatus 10 and/or the delivery engine 100 of the present
invention deliver a volatile material to the atmosphere in a continuous
manner. The term "volatile material" as used herein, refers to a material
that is vaporizable at room temperature and atmospheric pressure without
the need of an energy source. The volatile material may be a composition
comprised entirely of a single volatile material. The volatile material
may also be a composition comprised entirely of a volatile material
mixture (i.e. the mixture has more than one volatile component). Further,
it is not necessary for all of the component materials of the composition
to be volatile. Any suitable volatile material in any amount or form,
including a liquid or emulsion, may be used.

[0074] Liquid suitable for use herein may, thus, also have non-volatile
components, such as carrier materials (e.g., water, solvents, etc). It
should also be understood that when the liquid is described herein as
being "delivered", "emitted", or "released," this refers to the
volatilization of the volatile component thereof, and does not require
that the non-volatile components thereof be emitted.

[0075] The volatile material can be in the form of perfume oil. Most
conventional fragrance materials are volatile essential oils. The
volatile material can be a volatile organic compound commonly available
from perfumery suppliers. Furthermore, the volatile material can be
synthetically or naturally formed materials. Examples include, but are
not limited to: oil of bergamot, bitter orange, lemon, mandarin, caraway,
cedar leaf, clove leaf, cedar wood, geranium, lavender, orange, origanum,
petitgrain, white cedar, patchouli, neroili, rose absolute, and the like.
In the case of air freshener or fragrances, the different volatile
materials can be similar, related, complementary, or contrasting.

[0076] The volatile material may also originate in the form of a
crystalline solid, which has the ability to sublime into the vapor phase
at ambient temperatures or be used to fragrance a liquid. Any suitable
crystalline solid in any suitable amount or form may be used. For
example, suitable crystalline solids include but are not limited to:
vanillin, ethyl vanillin, coumarin, tonalid, calone, heliotropene, musk
xylol, cedrol, musk ketone benzohenone, raspberry ketone, methyl naphthyl
ketone beta, phenyl ethyl salicylate, veltol, maltol, maple lactone,
proeugenol acetate, evemyl, and the like.

[0077] It may not be desirable, however, for volatile materials to be
closely similar if different volatile materials are being used in an
attempt to avoid the problem of emission habituation. Otherwise, the
people experiencing the emissions may not notice that a different
material is being emitted. The different emissions can be provided using
a plurality of delivery systems each providing a different volatile
material (such as, musk, floral, fruit emissions, etc). The different
emissions can be related to each other by a common theme, or in some
other manner. An example of emissions that are different, but
complementary might be a cinnamon emission and an apple emission.

[0078] In addition to the volatile material of the present invention, the
delivery engine 100 may include any known malodor composition to
neutralize odors. Suitable malodor compositions include cyclodextrin,
reactive aldehydes and ionones.

[0079] While not wishing to be bound by theory, the continuous delivery of
a volatile material may be a function of various factors including
membrane pore size; membrane surface area; the physical properties of a
volatile material, such as molecular weight and saturation vapor pressure
("VP"); and the viscosity and/or surface tension of the composition
containing the volatile material.

[0080] The composition may be formulated such that the composition
comprises a volatile material mixture comprising about 10% to about 100%,
by total weight, of volatile materials that each having a VP at
25° C. of less than about 0.01 torr; alternatively about 40% to
about 100%, by total weight, of volatile materials each having a VP at
25° C. of less than about 0.1 torr; alternatively about 50% to
about 100%, by total weight, of volatile materials each having a VP at
25° C. of less than about 0.1 torr; alternatively about 90% to
about 100%, by total weight, of volatile materials each having a VP at
25° C. of less than about 0.3 tom In one embodiment, the volatile
material mixture may include 0% to about 15%, by total weight, of
volatile materials each having a VP at 25° C. of about 0.004 torr
to about 0.035 torr; and 0% to about 25%, by total weight, of volatile
materials each having a VP at 25° C. of about 0.1 ton to about
0.325 ton; and about 65% to about 100%, by total weight, of volatile
materials each having a VP at 25° C. of about 0.035 torr to about
0.1 ton. One source for obtaining the saturation vapor pressure of a
volatile material is EPI Suite®, version 4.0, available from U.S.
Environmental Protection Agency.

[0081] Two exemplary compositions comprising a volatile material mixture
having volatile materials of varying VPs are set forth below in Tables 1
and 2. These compositions are shown by way of illustration and are not
intended to be in any way limiting of the invention.

[0082] The viscosity of a volatile material may control how and when a
volatile material is delivered to the breathable membrane 140. For
example, less viscous compositions may flow faster than the more viscous
volatile materials. Thus, the membrane may be first wetted with the less
viscous materials. The more viscous volatile material, being slightly
less or of similar density with the less viscous phase, may remain in the
collection basin 112 via gravity. Thus, the less viscous volatile
material may be delivered to the breathable membrane 140 and emitted to
the atmosphere more quickly. To help prevent liquid from seeping through
the breathable membrane 140, volatile materials may have viscosities less
than about 23 cP and surface tension less than about 33mN/m.

[0083] In one embodiment, the composition containing a volatile material
may have a viscosity of about 1.0 cP to less than about 25 cP,
alternatively about 1.0 cP to less than about 23, alternatively about 1.0
cP to less than about 15 cP.

[0084] The composition containing a volatile material may be designed such
that the composition may include a surface tension of about 19 mN/m to
less than about 33 mN/m, alternatively about 19 mN/m to less than about
30 mN/m, alternatively about 19 mN/m to less than about 27 mN/m.

EXAMPLES

[0085] The following examples are not to be construed as limitations of
the present invention since many variations thereof are possible without
departing from its spirit and scope.

Example 1

[0086] In this example, two identical air freshening delivery engines are
designed utilizing a Daramic V5 membrane with an evaporative surface area
of approximately 34 cm2. Two perfume compositions, RJJ-577 and
RJJ-573-8, each having a volatile material mixture with volatile
materials of different VP ranges are tested in the air freshening
delivery engines for evaporation rates. The VP ranges of the volatile
materials are shown in Tables 3 and 4.

[0087] One delivery engine is loaded with 6000 mg of perfume composition
RJJ-577; the other with 6000 mg of perfume composition RJJ-573-8. RJJ-577
includes relatively higher VP components than RJJ-573-8. Each filled
delivery engine is weighed; weight is recorded. Both delivery engines are
placed into housings and held in a room at 21° C. At the times
indicated on FIG. 10, the delivery engine is weighed; weight recorded.
FIG. 10 shows that after about two weeks, the evaporation rate of RJJ-577
has almost flattened which would then require another delivery engine.
This would be costly and may be viewed as burdensome by consumers. On the
other hand, perfume RJJ-573-8 with a microporous membrane delivers
consistent linear intensity over a longer period of time.

Example 2

[0088] In this example, two air freshening delivery engines are
constructed utilizing different membranes. Each is tested for evaporation
rates using RJJ-573-8, which was utilized in Example 1. 6000 mg of
RJJ-573-8 is loaded into a delivery engine with a low density
polyethylene membrane (LDPE) having an average pore size of about 40
microns. 6000 mg of RJJ-573-8 is loaded into a delivery engine having a
Daramic V5 microporous membrane. As can be seen from FIG. 11, the
microporous membrane is much more efficient in releasing the relatively
low vapor pressure perfume than the LDPE membrane. Thus, utilizing a
microporous membrane in accordance with the present invention delivers
higher intensities of lower vapor pressure (i.e. more pleasing "base
note" perfume raw materials can be delivered).

[0089] Every numerical range given throughout this specification will
include every narrower numerical range that falls within such broader
numerical range, as if such narrower numerical range were all expressly
written herein. Further, the dimensions and values disclosed herein are
not to be understood as being strictly limited to the exact numerical
values recited. Instead, unless otherwise specified, each such dimension
is intended to mean both the recited value and a functionally equivalent
range surrounding that value. For example, a dimension disclosed as "40
mm" is intended to mean "about 40 mm."

[0090] Every document cited herein, including any cross referenced or
related patent or application, is hereby incorporated herein by reference
in its entirety unless expressly excluded or otherwise limited. The
citation of any document is not an admission that it is prior art with
respect to any invention disclosed or claimed herein or that it alone, or
in any combination with any other reference or references, teaches,
suggests or discloses any such invention. Further, to the extent that any
meaning or definition of a term in this document conflicts with any
meaning or definition of the same term in a document incorporated by
reference, the meaning or definition assigned to that term in this
document shall govern.

[0091] While particular embodiments of the present invention have been
illustrated and described, it would be obvious to those skilled in the
art that various other changes and modifications can be made without
departing from the spirit and scope of the invention. It is therefore
intended to cover in the appended claims all such changes and
modifications that are within the scope of this invention.